Internal States of Hadrons in Relativistic Reference Frames

TL;DR

This paper demonstrates that the internal state of a composite particle remains unchanged under Lorentz transformations, implying no Lorentz contraction occurs for spherically symmetric states in relativistic reference frames.

Contribution

It shows that the internal state of a composite particle in its rest frame remains invariant under Lorentz transformations, challenging the common assumption of Lorentz contraction for such states.

Findings

Internal states remain unchanged across inertial frames.

Spherically symmetric states do not undergo Lorentz contraction.

Application to hadron scattering as bound quark states.

Abstract

The internal state of a composite particle and its transformation, when changing from the reference frame, where this composite particle is at rest, to a reference frame, where it moves relativistically, have been considered. It is supposed that the internal state of the composite particle in its rest frame can be considered in the non-relativistic approximation. This internal state is shown to remain the same, when changing from one inertial reference frame to another one. In other words, a particle that is spherically symmetric in its rest frame does not change its form in any other reference frame and does not undergo the Lorentz contraction in the direction of motion of any reference frame with respect to the rest one. A possible application of the results obtained to describe the scattering of hadrons considered as bound states of quarks has been discussed.